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Simple Summary: In this study, we carried out global proteomic profiling of esophageal squamous cell carcinoma and adjacent non-neoplastic esophageal tissue to identify putative biomarkers and targets. We identified several differentially expressed proteins including PDPN, TOP2A, POSTN and MMP2 that were overexpressed in ESCC. We also identified overexpression of SOX2, TP63, IGF2BP2 and RNF13 that are encoded by 3q26 region, a known hotspot region in ESCC. Synoviolin 1 (SYVN1), a protein involved in endoplasmic reticulum (ER)-associated degradation and other ER stress response proteins were overexpressed in ESCC. SYVN1 could be a potential therapeutic target in ESCC. Esophageal squamous cell carcinoma (ESCC) is a heterogeneous cancer associated with a poor prognosis in advanced stages. In India, it is the sixth most common cause of cancer-related mortality. In this study, we employed high-resolution mass spectrometry-based quantitative proteomics to characterize the differential protein expression pattern associated with ESCC. We identified several differentially expressed proteins including PDPN, TOP2A, POSTN and MMP2 that were overexpressed in ESCC. In addition, we identified downregulation of esophagus tissue-enriched proteins such as SLURP1, PADI1, CSTA, small proline-rich proteins such as SPRR3, SPRR2A, SPRR1A, KRT4, and KRT13, involved in squamous cell differentiation. We identified several overexpressed proteins mapped to the 3q24-29 chromosomal region, aligning with CNV alterations in this region reported in several published studies. Among these, we identified overexpression of SOX2, TP63, IGF2BP2 and RNF13 that are encoded by genes in the 3q26 region. Functional enrichment analysis revealed proteins involved in cell cycle pathways, DNA replication, spliceosome, and DNA repair pathways. We identified the overexpression of multiple proteins that play a major role in alleviating ER stress, including SYVN1 and SEL1L. The SYVN1/SEL1L complex is an essential part of the ER quality control machinery clearing misfolded proteins from the ER. SYVN1 is an E3 ubiquitin ligase that ubiquitinates ER-resident proteins. Interestingly, there are also other non-canonical substrates of SYVN1 which are known to play a crucial role in tumor progression. Thus, SYVN1 could be a potential therapeutic target in ESCC. [ABSTRACT FROM AUTHOR]

• Chronic diesel particulate extract (DPE)/its vapor cause global proteomic changes. • DPE/DPE vapor alter skin integrity related proteins in primary skin keratinocytes. • DPE vapor affects OXPHOS and cell migration associated proteins in skin cells. • DPE/DPE vapor treatment in 3D skin recapitulates their effects on 2D culture. • Vitamin E partially restores altered proteins in DPE/vapor exposed cells. Skin acts as a protective barrier against direct contact with pollutants but inhalation and systemic exposure have indirect effect on keratinocytes. Exposure to diesel exhaust has been linked to increased oxidative stress. To investigate global proteomic alterations in diesel particulate extract (DPE)/ its vapor exposed skin keratinocytes. We employed Tandem Mass Tag (TMT)-based proteomics to study effect of DPE/ DPE vapor on primary skin keratinocytes. We observed an increased expression of oxidative stress response protein NRF2, upon chronic exposure of primary keratinocytes to DPE/ its vapor which includes volatile components such as polycyclic aromatic hydrocarbons (PAHs). Mass spectrometry-based quantitative proteomics led to identification 4490 proteins of which 201 and 374 proteins were significantly dysregulated (≥1.5 fold, p ≤ 0.05) in each condition, respectively. Proteins involved in cellular processes such as cornification (cornifin A), wound healing (antileukoproteinase) and differentiation (suprabasin) were significantly downregulated in primary keratinocytes exposed to DPE/ DPE vapor. These results were corroborated in 3D skin models chronically exposed to DPE/ DPE vapor. Bioinformatics analyses indicate that DPE and its vapor affect distinct molecular processes in skin keratinocytes. Components of mitochondrial oxidative phosphorylation machinery were seen to be exclusively overexpressed upon chronic DPE vapor exposure. In addition, treatment with an antioxidant like vitamin E partially restores expression of proteins altered upon exposure to DPE/ DPE vapor. Our study highlights distinct adverse effects of chronic exposure to DPE/ DPE vapor on skin keratinocytes and the potential role of vitamin E in alleviating adverse effects of environmental pollution. [ABSTRACT FROM AUTHOR]

Highlights • Chronic exposure to diesel particulate extract/ its vapor cause global proteomic alterations in primary skin keratinocytes. • DPE/DPE vapor alter proteins involved in maintaining skin integrity in primary skin keratinocytes. • DPE vapor affects proteins associated with OXPHOS and cell migration in skin keratinocytes. • Similar effects are observed upon DPE/DPE vapor treatment in 2D and 3D skin model. • Vitamin E partially restores altered proteins in DPE/vapor exposed skin keratinocytes. Abstract Background Skin acts as a protective barrier against direct contact with pollutants but inhalation and systemic exposure have indirect effect on keratinocytes. Exposure to diesel exhaust has been linked to increased oxidative stress. Objective To investigate global proteomic alterations in diesel particulate extract (DPE)/its vapor exposed skin keratinocytes. Methods We employed Tandem Mass Tag (TMT)-based proteomics to study effect of DPE/DPE vapor on primary skin keratinocytes. Results We observed an increased expression of oxidative stress response protein NRF2, upon chronic exposure of primary keratinocytes to DPE/its vapor which includes volatile components such as polycyclic aromatic hydrocarbons (PAHs). Mass spectrometry-based quantitative proteomics led to identification 4490 proteins of which 201 and 374 proteins were significantly dysregulated (≥1.5 fold, p ≤ 0.05) in each condition, respectively. Proteins involved in cellular processes such as cornification (cornifin A), wound healing (antileukoproteinase) and differentiation (suprabasin) were significantly downregulated in primary keratinocytes exposed to DPE/DPE vapor. These results were corroborated in 3D skin models chronically exposed to DPE/DPE vapor. Bioinformatics analyses indicate that DPE and its vapor affect distinct molecular processes in skin keratinocytes. Components of mitochondrial oxidative phosphorylation machinery were seen to be exclusively overexpressed upon chronic DPE vapor exposure. In addition, treatment with an antioxidant like vitamin E partially restores expression of proteins altered upon exposure to DPE/DPE vapor. Conclusions Our study highlights distinct adverse effects of chronic exposure to DPE/DPE vapor on skin keratinocytes and the potential role of vitamin E in alleviating adverse effects of environmental pollution. [ABSTRACT FROM AUTHOR]

Keratin 8/18, the predominant keratin pair of simple epithelia, is often aberrantly expressed in various squamous cell carcinomas (SCCs) including skin SCC. Its aberrant expression is correlated with increased invasiveness and poor prognosis of the same, although the underlying mechanism is still unclear. A previous report from our laboratory has shown K8‐mediated regulation of α6β4 integrin signaling and thereby tumorigenic potential of oral SCC‐derived cells. Another study on transgenic mouse model has shown that during skin carcinogenesis, K8 favors conversion of papillomas toward malignancy. In order to understand the role of K8 and allied mechanism in skin SCC, K8 was stably knocked down in a skin epidermoid carcinoma‐derived A431 cells. K8 downregulation significantly reduced the tumorigenic potential of these cells. In agreement with our phenotypic data, differential quantitative proteomics followed by IPA analysis showed altered expression of many proteins associated with biological functions including ‘Cancer’, ‘Cellular movement’, ‘Cell death and survival’, and ‘Cellular morphology’. Some of these proteins were TMS1, MARCKSL1, RanBP1, 14‐3‐3γ, Rho‐GDI2, etc. Furthermore, to our surprise, there was a significant reduction in K17 protein stability upon loss of K8, probably due to its caspase‐mediated degradation. This was supported by altered TMS1‐NF‐κB signaling, leading to increased apoptotic sensitivity of A431 cells which in turn affected ‘Cell death and survival’. Moreover, MARCKSL1‐Paxillin1‐Rac axis was found to be deregulated bestowing a possible mechanism behind altered ‘Cellular movement’ pathway. Altogether our study unravels a much broader regulatory role of K8, governing multiple signaling pathways and consequently regulating oncogenic potential of skin SCC‐derived cells. Database: Proteome Xchange Consortium via PRIDE database (dataset identifier PXD007206). [ABSTRACT FROM AUTHOR]

Dicer is a crucial RNase III enzyme in miRNA biogenesis pathway. Although numerous studies have been carried out to investigate the role of miRNAs and Dicer in the regulation of biological processes, few studies have examined proteomic alterations upon knockout of Dicer. We employed a Cre--loxP-based inducible knockout mouse system to investigate the proteome regulated by Dicer-dependent miRNAs. We utilized spiked liver lysates from metabolically labeled mice to quantify the subtle changes in the liver proteome upon deletion of Dicer. We identified 2137 proteins using high resolution tandem mass spectrometry analysis. The upregulated proteins included several enzymes involved in peroxisomal β-oxidation of fatty acids and a large majority of the upregulated proteins involved in lipid metabolism were known PPARα targets. MRM-based assays were carried out to confirm the upregulation of enzymes including peroxisomal bifunctional enzyme, phosphoenolpyruvate carboxykinase 1, cytochrome P450 3A13, cytochrome P450 3A41 and myristoylated alanine-rich protein kinase C substrate. Further, miRNA-124 which is predicted to regulate expression of peroxisomal bifunctional enzyme was confirmed to be downregulated in the Dicer knockout mice. Our study demonstrates the strength of coupling knockout mouse models and quantitative proteomic strategies to investigate functions of individual proteins in vivo. [ABSTRACT FROM AUTHOR]

Highlights: [•] Quantitative proteomic analysis of gallbladder cancer. [•] LC–MS/MS analysis using Fourier transform high resolution mass spectrometry. [•] 2575 proteins identified including several upregulated lysosomal proteins. [•] Prosaposin and transgelin validated as candidate markers using tissue microarrays. [Copyright &y& Elsevier]

Bladder carcinoma (BC) incidence and mortality rates are increasing worldwide. The development of novel therapeutic strategies is required to improve clinical management of this cancer. Aberrant protein expression may lead to cancer initiation and progression. Therefore, the identification of these potential protein targets and limiting their expression levels would provide alternative treatment options. In this study, we utilized a liquid-chromatography tandem mass spectrometry-based global proteomics approach to identify differentially expressed proteins in bladder cancer cell lines. A total of 3913 proteins were identified in this study, of which 479 proteins were overexpressed and 141 proteins were downregulated in 4 out of 6 BC cell lines when compared with normal human urothelial cell line (TERT-NHUC). We evaluated the role of UDP-N-acetylhexosamine pyrophosphorylase (UAP1) in bladder cancer pathogenesis. The silencing of UAP1 led to reduction in proliferation, invasion, colony formation and migration capability of bladder cancer cell lines. Thus, our study reveals UAP1 as a promising therapeutic target for bladder cancer. [ABSTRACT FROM AUTHOR]